Matousec are professionals who really know how to put firewalls through their paces and really test their "leakage" ability.
I might comment on a firewall product's ease of usage for the average home user, or it's GUI interface, or stability or (my personal) system utilization. I might myself run a slew of leak-tests in a virtual machine to see how they work against a firewall. But when it comes to really technically evaluating a firewall product, I trust the Matousec team.
So their site-feed announced more leak-testing results I hopped on over to see what they had dug up. And I wasn't disappointed!
In total, Matousec tested the outbound leakage efficacy of an amazing 33 personal firewall products. Wow.
I won't steal their thunder by taking their work and posting it here, go check it out yourself on Matousec's great results table. They've worked hard and it shows. Props to them.
However, for a teaser...two products (both free with one I really recommend) got "Excellent" marks.
Another seven received "Very Good" scores.
Four firewalls got "Good" marks.
Eleven got "Poor" to "Very Poor" ratings.
And nine were found to offer no outbound leakage protection at all.
Now, that's not to say that any of these firewall products fail to provide acceptable inbound protection. I'm sure they all do and for many users that is more than enough.
However, there remains growing threats from botnets, malware, trojans and the like trying to take over the bandwidth and computing power to pump spam and ilk into the Net. Unless you already have a strong perimeter of personal computing defenses (user --> hardware firewall --> software firewall --> anti-virus software --> anti-malware software --> process level/HIPS monitoring --> rootkit scanner --> regular system/application patching) and scan your system regularly, it makes sense to use a firewall that provides both inbound outbound protection.
Read the posts, make a choice.
Just please stay informed and safe.